1. FIELD OF THE INVENTION
The present invention relates in general to safety ski bindings and has specific reference to heel hold-down devices adapted releasably to hold the heel portion of a ski boot against unnecessary movements on a ski or a base plate mounted thereon.
2. DESCRIPTION OF THE PRIOR ART
This invention is concerned more particularly with heel hold-down devices of the type wherein the heel retaining member is carried by a pair of lateral arms mounted for free pivotal movement about two horizontal axes. A heel hold-down device of this character is disclosed in my prior U.S. Pat. No. 3,249,365.
In this prior art device the heel retaining member is rotatably mounted about a horizontal transverse axis overlying the ski surface, behind the area normally occupied by the boot, and a spring-loaded mechanism constantly urges this member to the position enabling it to hold the heel of the ski boot against movement.
However, the arrangement is such that the boot heel can be lifted momentarily under normal skiing conditions. In this case, the lateral arms of the heel hold-down device pivot slightly upwards, but the spring-loaded mechanism controlling the retaining member subsequently restores the assembly to its initial position. Yet, in case of excessive effort due notably to a forward fall of the skier, the pivotal movement of the lateral arms continues until the retaining member escapes from the boot heel to release the boot completely.
To facilitate the initial operation consisting in positioning and locking the ski boot, locking means are provided as a rule for holding the retaining member of a heel hold-down device in its normal position. This locking system comprises a manually operable latch, for examples a bow-shaped member adapted to act as a stop member bearing against the ski surface. Besides, this latch is also capable of holding the retaining member of the heel ski binding against motion when transporting the skis.
However, the skier must necessarily be able to actuate this latch manually in order to bring same to its heel hold-down position. On the other hand, this latch must subsequently be retracted to permit the subsequent normal operation of the heel hold-down device. Now this retraction may if desired be controlled by the heel retaining member itself when the latter is in its operative or retaining position. However, in this case a particular arrangement of this member and an accurate adjustment of the position of the latch member are required, otherwise the latch member might fail from retracting to its non-interfering position, thus preventing the normal operation of the corresponding heel hold-down device.